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As a measure for contrasting pine wilt disease, which caused serious damage in Japanese black pine (Pinus thunbergii Parl.) by the pine wood nematode (Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle), resistant trees have been widely planted in Japan. The propagation of resistant trees using cuttings obtained from healthy stock plants and inoculated with pine wood nematode is expected to further increase in the next future. To improve the cutting propagation of Japanese black pine trees resistant to pine wilt disease, the factors associated with rooting and root volume were investigated. The type of cutting and the crown position of stock plants from which cuttings were taken, were markedly associated with rooting. The crown position did not show significant interactions with any other investigated factor, while fresh weight of cuttings and their number of winter buds did not affect rooting. The rooting percentage was markedly higher for cuttings taken from the lower crown than for those from the upper crown, as already reported for other coniferous tree species. The length of the longest needle was significantly correlated with the root volume of cuttings, and showed significantly interactions with crown position and fresh weight of cuttings. Such correlation suggests that the growth of needles can be considered a useful predictor in the assessment of the root volume of cuttings during the propagation period, allowing growers to transplant rooted cuttings at the appropriate time without excavating or uprooting. These findings may contribute to the improvement of cutting propagation of Japanese black pine.

The advanced fabrication method named advanced multi-step brazing (AMSB) has been developed for fabrication of a tungsten (W)/copper alloy divertor heat removal component in a fusion reactor. The principle of AMSB is repetitive application of the advanced brazing technique (ABT). The ABT was originally developed in our previous work for jointing of W and oxide dispersion strengthened copper alloy (ODS-Cu: GlidCop®) with the BNi-6 (Ni-11%P) filler material. The special feature of the AMSB is that the leak-tight joint of GlidCop® (GlidCop®/GlidCop®) and of stainless steel (SUS) and GlidCop® (SUS/GlidCop®) can be realized by application of the ABT. Therefore, the AMSB enables production of a leak-tight sealing structure with the appropriate lid material such as GlidCop® or SUS for a pre-processed rectangle-shaped cooling flow path channel. The rectangle-shaped cooling flow path channel has an advantage regarding its heat removal capability. Another special feature of the AMSB is that the physical properties of the AMSB joint has strong tolerance against the repetitive brazing heat cycle. Thus, repetitive application of the ABT does not cause any undesired effects on the leak tightness of the GlidCop®/GlidCop® and the SUS/GlidCop®. The new AMSB type component with the rectangle-shaped fluid flow path and the V-shaped staggered rib structure were successfully produced; therein a pre-processed rectangle-shaped cooling flow path channel was sealed with a GlidCop® and SUS lid structure with leak-tight conditions. The component showed excellent heat removal capability under reactor-relevant conditions with ∼30 MW m−2. [ABSTRACT FROM AUTHOR]

In this study, hydrogen electron plasma is irradiated on an aluminum plate, and negative hydrogen ions are produced on the plate surface. Hydrogen ionic plasma is maintained near the surface, where a deflection magnetic field is applied using a pair of magnets in the vicinity of the surface. When no magnetic field is applied, ionic plasma is not formed. The interface position between the ionic and the electron plasma depends on the quantity of negative ions produced and the deflection magnetic flux density. The deflection magnetic field that controls the electron flux toward the surface, while maintaining quasi-neutrality, is indispensable for the formation of ionic plasma. [ABSTRACT FROM AUTHOR]

Woody biomass is an important parameter in forestry and forest research. In order to estimate of woody biomass, it is important to precisely and efficiently calculate section areas and volumes of tree stems in the forest. In this paper, we propose a method for calculating the cross-sectional area and the stem volume of trees from point clouds captured using the terrestrial laser scanner. In our method, each point cloud is converted into a wireframe model, and cross-section points are calculated as intersection between the wireframe and the horizontal planes placed at equal intervals. Cross-sectional shapes on each horizontal plane are approximated as n-sided polygons and refined using the subdivision scheme. The section areas and stem volumes are calculated using the subdivision curves of stem contours. In our evaluation, our method could calculate section areas and stem volumes of trees with sufficient accuracy in practical use. [ABSTRACT FROM AUTHOR]

We prepared multiferroic Y-type hexaferrite Ba0.5Sr1.5Zn2Fe12O22 ceramics and compared their magnetic and dielectric properties with single crystal. Magnetic susceptibility and microwave resonance measurement revealed magnetic phase transition at TC=312 K, similar as in single crystal. Ferroelectric (FE) phase can be induced by external magnetic field in all investigated samples and the phase diagram in ceramics qualitatively resembles that of the single crystal. The range of magnetic fields, where the FE phase is induced, broadens after annealing of single crystal. Ceramics quenched after sintering exhibit several orders of magnitude lower conductivity than the single crystal. Heavily damped magnetic resonance was discovered in terahertz spectra at 10 K and its frequency softens below 5 GHz near TC. Number and symmetry of observed infrared (IR) and Raman active phonons correspond to paraelectric phase with D3d5 hexagonal structure. No evidence for a structural phase transition was found in the IR and Raman spectra on cooling (in zero magnetic field) or in the room-temperature IR spectra with external static magnetic field up to 0.3 T. [ABSTRACT FROM AUTHOR]

In this study, a hydrogen ionic plasma with relatively low residual fractional electron concentration (ne/n+ ∼ 10−2) is generated using an aluminum plasma grid for the production of negative hydrogen ions and a control grid for negative ion extraction and electron removal. The ionic plasma is composed of negative and positive ions, containing molecular ions. Negative ions are in part produced using positive ions with several electron volts. A positive ion beam with 50 eV or more contributes to increase the density of the ionic plasma. The positive ion beam energy and the control grid bias voltage are tuned in such a way that a high-density ionic plasma is maintained. [ABSTRACT FROM AUTHOR]

Spin-chiral domain structures near a cleaved crystal face of a magnetoelectric helimagnet, Ba 0.5 Sr 1.5 Zn 2 Fe 12 O 22 , were examined after various magnetic and electric field-cooling procedures by means of the scanning resonant X-ray microdiffraction technique using circularly polarized X-rays. We have found that the application of a magnetic field (1–2 k Oe) during the field-cooling procedure stabilizes one of the handedness among the two spin-chiral states (left- or right-handed screw structure) and makes nearly a single spin-chiral domain in the vicinity of the cleaved crystal face. However, it makes the degree of the spin chirality spatially inhomogeneous even within a domain. We discuss the observed field-cooling effect in terms of possible formation of spin-chiral domains with “stripe-type” domain walls accompanied by randomly-distributed ferromagnetic islands. [ABSTRACT FROM AUTHOR]